PHP/Math/acos
float acos ( float num ) calculates the arc cosine value
<source lang="html4strict">
<?
$acos1 = acos(0.4346); $acos2 = acos(cos(80));
?>
</source>
<source lang="html4strict">
<?
$acos1 = acos(0.4346); $acos2 = acos(cos(80));
?>
</source>